Waterproof muffler for vertical exhausts



OCt' A G C S WATERPROOF MUFFLER FOR VERTICAL EXHAUSTS Filed Aug. 1, 1951 United States Patent Ofiice WATERPROOF MUFFLER FOR VERTICAL EXHAUSTS Alpha G. Cheairs, San Antonio, Tex. Application August 1, 1951, Serial No. 239,794

1 Claim. (Cl. 181-53) This invention relates to a waterproof muifier for a vertical exhaust, and more particularly to the exhaust pipes of heavy equipment such as is employed in construction work and the like.

Mobile power plants such as are used in construction freely to atmosphere with the result that in areas where heavy rainfall is encountered water will find its way into the open upper ends of the exhaust pipes of such equipment, and Where the rainfall continues for protracted periods and the equipment is not capable of being used, the collection of water within the exhaust pipes becomes sufficiently great to cause injury to the expensive equipment.

Efforts have been made to prevent the entrance of water into the power plant of a piece of equipment by capping the upper open end of the exhaust pipe with an ordinary tin can, but owing to the fact that such cans are subject to loss and destruction, such expedients have not proven altogether satisfactory.

The efforts to produce more satisfactory methods of closing or draining the open upper ends of the exhaust pipes of internal combustion engine power plants are exemplified in Patents 2,420,700 and 2,446,631. Owing to various objections, however, devices of the nature disclosed in the aforesaid patents have not been widely adapted, particularly due to the fact that such structures either create considerable back pressure which must be overcome by the pressure of the exhaust gases, or allow leakage of the exhaust gases downwardly with the resultant ill eifects on those working in the vicinity of the power plants.

The primary object of this invention is to effectively protect a power plant from injury by reason of the introduction of Water into the upwardly directed exhaust pipe.

Another important object is to insure that the exhaust gases passing upwardly through the exhaust pipe and which are discharged through the upper end thereof will when finally released to atmosphere be discharged in an upward direction and away from persons in the vicinity of the power plant.

The above and other objects may be attained by employing this invention which embodies among its features a perforated head carried by the upper end of the exhaust pipe through the perforations of which the exhaust gases are conducted, a hood carried by the head in concentric spaced relation thereto and defining with the head a downwardly opening annular gas discharge passage, and an annular deflector carried by the exhaust pipe below the 2,721,619 Patented Oct. 25, 1955 lower end of the hood and extending upwardly in concentric spaced relation to the hood and defining with said hood an annular upwardly opening passage through which the exhaust gases are directed upwardly to atmosphere.

Other features include terminating the deflector below the lowermost opening in the hood to prevent water which may accumulate in the deflector from entering the head and the exhaust pipe.

In the drawings,

Fig. 1 is a side view of a conventional tractor having a vertically disposed exhaust pipe and showing this improved protective device in place,

Fig. 2 is a fragmentary enlarged side view of the exhaust pipe showing this improved protective device in section, and

Fig. 3 is a horizontal sectional view taken substantially along the line 33 of Fig. 2.

Referring to the drawings in detail a conventional tractor 1%) is equipped with a conventional power plant (not shown) having a vertically extending exhaust pipe .12 which under normal circumstances opens upwardly to atmosphere.

The exhaust pipe 12 has connected to its upper end in any suitable manner a tubular body 14 carrying at its upper end a head 16 which is provided with a multiplicity of perforations 18 forming discharge openings for the exhaust gases which in their aggregate preferably exceed the cross sectional area of the exhaust pipe 12. The head 16 may be dome shaped as suggested in the drawings, or may be in any other suitable convenient shape which will i readily permit the passage of the exhaust gases through the openings 18.

Supported on the head 16 in any conventional manner is a hood 20 which in the form shown in the drawings is dome shaped and carries a depending skirt 22 which lies in concentric spaced relation to the head 16 and cooperates with the tubular body 14 in forming a downwardly opening annular passage 24 into which the exhaust gases passing through the exhaust pipe 14 are introduced through the passages 18. The skirt 22 is of considerable length, and the passage 24 has a cross section which is preferably in excess of the cross sectional area of the openings 18 in order to offer as liitle resistance to the passage of the exhaust gases as possible.

Supported on the cylindrical body 14 below the lower end of the skirt 22 is a collar 26 which carries an outstanding annular flange 23, the upper surface of which is preferably concaved as at 30 so that exhaust gases passing downwardly through the passage 24 will be turned upwardly upon encountering the flange 28 as will be readily understood upon reference to the drawings. Carried by the flange 28 in concentric spaced relation to the hood 20 is a cylindrical upstanding wall 32 which lies in concentric spaced relation to the hood 20 and defines with the hood an annular upwardly opening passage 34 through which the exhaust gases directed downwardly in the passage 24 are directed upwardly and escape to atmosphere from the upper end thereof. It is important that the wall 32 terminate below the lowermost opening 18 in the head 16 so that any Water that may accumulate in the passage 34 and passage 24 will be discharged over the open upper end of the passage 34 before it can reach the lowermost opening 18.

In the preferred form of the invention, the flange 23 is provided with a drain opening 36 in which any suitable drain cock 38 may be fitted so that Whenever desired, water which has collected within the passage 34 may be discharged therefrom by opening the drain cock 38. in the preferred form of the invention the cross sectional area of the passage 34 is greater than the cross sectional area of the passage 24 so as to allow for the free discharge of gases therethrough.

In use it will be understood that with the device mounted on the upper end of the exhaust pipe 12, the exhaust gases passing through the pipe 12 will enter the tubular body 14 to be discharged through the openings 13 in the head 16 into the downwardly opening passage 24, from which they enter the upwardly opening passage'34 and by reason of the concave upper'surface 30 of the flange 28'little or no resistance to their reversal of movement will be encountered. By reason of the relative length of the cylindrical wall 32, it will be evident that the gases passing upwardly through the passage 34 will continue on their upward direction of movement and will not tend to be discharged downwardly to pollute the atmosphere in the vicinity of those working around the piece of equipment. Also because of the fact that the upper open end of the exhaust 12 is closed by the dome shaped hood 20 water cannot enter the interior of the exhaust pipe to injure the engine to which it is connected, and any water that may collect in the passage 34 cannot rise above the upper edge of the wall 32 to enter the openings 18, particularly in view of the fact that the water will spill outwardly over the upper edge of the wall 32, and the discharge opening for the water is so much greater than the combined areas of the lowermost openings 18 that there will be no tendency for the water to reach these openings.

While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.

What is claimed is:

In an internal combustion power plant of the type having an exhaust system and a vertically extending elongated exhaust pipe connected to said system through which exhaust gases from the power plant are conducted to atmosphere above the heads of persons in the vicinity of the power plant, means for preventing water from entering the exhaust pipe comprising a concavo-convex head carried by the upper end of the exhaust pipe, said head having a plurality'of spaced apart openings extending transversely therethrough, the sum of the cross sectional area of the openings being in excess of the cross sectional area of the exhaust pipe to provide for the free passage of the exhaust from said exhaust pipe and head, a concave-convex hood carried by and extending downwardly from the head centrally overlying and closing said exhaust pipe and disposed peripherally in concentric spaced relation to the head and to the exhaust pipe said hood defining with the head and the exhaust pipe a downwardly opening annular space having a cross sectional area in excess of the cross sectional area of the openings, an annular deflector carried by the exhaust pipe below the lower end of the hood, and said deflector extending upwardly in concentric spaced relation to the hood and defining with said hood an annular upwardly opening space having a cross sectional area in excess of the cross sectional area of the downwardly opening space, and said deflector terminating below the lowermost opening in the head and opening to the atmosphere below said exhaust pipe.

References Cited in the file of this patent UNITED STATES PATENTS 830,660 Goldman Sept. 11, 1906 990,686 Troike Apr. 25, 1911 1,291,271 Tvedt Ian. 14, 1919 1,774,178 Holdsworth Aug. 26, 1930 1,845,015 Balough Feb. 16, 1932 2,363,236 Fluor Nov. 21, 1944 FOREIGN PATENTS 450 Great Britain Feb. 25, 1904 492,183 Germany Feb. 20, 1930 388,323 Great Britain Feb. 23, 1933 

